The present invention relates to sewing machines that are provided with a sequin feeder device and that sew sequins onto a sewing workpiece while severing or cutting sequins from a ribbon or strip of continuously-connected sequins (hereinafter referred to as “continuous sequin strip”), and more particularly to a technique for accelerating timing for cutting off a sequin from the continuous sequin strip.
One example of sequin feeder devices for use in sewing machines is known from Japanese Patent Application Laid-open Publication No. 2004-167097. The conventionally-known sequin feeder device disclosed in the No. 2004-167097 publication includes a feed mechanism for feeding a continuous sequin strip, by a predetermined pitch corresponding to a size of one sequin at a time. FIG. 9 shows the conventionally-known sequin feeder device with the feed mechanism in enlarged scale. The conventionally-known sequin feeder device pays out or lets out a continuous sequin strip 50 from a reel having the continuous sequin strip 50 wound thereon, then places a leading portion of the continuous sequin strip 50 on the upper surface of a support plate 51, then feeds out the leading portion of the continuous sequin strip 50 by a predetermined pitch through advancing and retracting movement of a feed lever 52, and then sews one sequin onto a sewing workpiece H while cutting off the sequin from the continuous sequin strip 50.
In the sewing machine provided with the conventionally-known sequin feeder device, cutting-off of the sequin is effected through cooperation between a movable cutter blade 54 pivotably disposed on an end portion of the support plate 51 and a fixed cutter blade 55 fixedly disposed on the end portion of the support plate 51. As a needle bar 53 descends in response to sewing operation, a sewing needle 56 passes through a needle passage hole of a fed-out sequin, after which a needle clamp 57 abuts against the movable cutter blade 54. FIG. 10 shows the needle clamp 57 having brought into abutting engagement with the movable cutter blade 54. As the needle bar 53 further descends from the state shown in FIG. 10, the movable cutter blade 54 is caused to pivot, so that the sequin is cut off from the continuous sequin strip 30 slightly before the needle bar 53 reaches its bottom dead point. Namely, the sequin is cut off at a stage where the sewing needle 56 has pierced the sewing workpiece H to a considerable degree as shown in FIG. 10. The thus-cut-off sequin falls onto the sewing workpiece H by being guided by the sewing needle 56 passed through the needle passage hole of the cut-off sequin, and then it is sewn onto the sewing workpiece H through subsequent sewing operation.
Namely, in the sewing machine provided with the conventionally-known sequin feeder device, the sequin is cut off from the continuous sequin strip near the bottom dead point of the needle bar when the sewing needle has passed deeply through the needle passage hole of the sequin. At that time, the sewing needle or a sewing thread passed through the sewing needle may undesirably contact the peripheral edge of the needle passage hole of the sequin due to vibration of the sewing machine, deformation of the sewing needle caused as the needle pierces the sewing workpiece, etc. If the sewing needle, descends with the sewing needle or sewing thread contacting the peripheral edge of the needle passage hole of the sequin, the fed-out sequin may be undesirably pressed downward together with the sewing thread as shown in FIG. 11. Consequently, the continuous sequin strip would be let out or pulled out excessively, so that, an actual sequin cutting position of the sequin strip would be undesirably deviated from a predetermined sequin cutting position. Further, if the sewing needle descends with the sewing thread kept contacting the peripheral edge of the needle passage hole of the sequin, the sewing thread would scrape against the peripheral edge of the needle passage hole of the sequin, so that the sewing thread may undesirably get frayed or broken. Particularly, in a case where the sequin to be sewn is of a small size, the needle passage hole of the sequin would naturally have a small diameter or size, and thus, the aforementioned inconveniences tend to occur easily.